As ice retreats, frozen mosses emerge to tell climate change tale

Dating of plants suggests summer’s hotter now than it’s been in at least 45,000 years, if not longer

ICE FREED Geologist Kurt Refsnider, now at Prescott College in Arizona, collects mosses revealed by retreating ice on Canada’s Baffin Island. Radiocarbon dates for the mosses suggest the region has less ice cover now than it did 45,000 years ago.

G. Miller

SEATTLE — Some mosses in the eastern Canadian Arctic, long entombed in ice, are now emerging into the sunlight. And the radiocarbon ages of those plants suggest that summertime temperatures in the region are the warmest they’ve been in tens of thousands of years.